You said you wanted to use LDAP for authentication (and authorization).
You can use Kerberos for authentication and LDAP for authorization.
LDAP authentication uses the userPassword attribute. Kerberos does not
use it as a password.

But even with Kerberos for authentication and LDAP for authorization
the userPassword will be tested to see if it is locked: *LK*, and root
on the server must be able to access the userPasswrord attribute in LDAP.

If you want to get responses from the list, you need to give more information.

On the server:
sshd -p 2222 -ddd

Then on the client:
ssh -p 2222 -l ldapusr authdns.nits.ac.in

Send the output of these two traces,
the /etc/pam/pam.conf, or the /etc/pam.d/ssh*
the /etc/nsswitch.conf
the sshd_config
the ssh_config on the client.